Synthesis in vitro of glycosaminoglycans in regenerating rat liver.
Chronic liver damage is accompanied by both liver cell multiplication and stimulated synthesis of proteoglycans, but the relationship between the two biochemical processes has not been investigated so far. We found that the incorporation of [14C]glucosamine into total glycosaminoglycans of rat liver slices from regenerating tissue is depressed by about 50% 1 and 3 days after operation if referred to that measured in sham-operated control liver slices. 6 h after partial hepatectomy [14C]glucosamine incorporation into glycosaminoglycans is stimulated by more than 30% in relation to sham operated livers. The proportional rates of synthesis of heparan sulfate and chondroitin sulfate (about 8:1) did not change in regenerating liver tissue. Furthermore, there was no difference in the intracellular uptake of [14C]glucosamine by rat liver slices from sham operated and partially hepatectomized rats; the pool size of UDP-N-acetylhexosamine was only slightly larger (about 14%) under the latter experimental condition. We conclude that liver regeneration by itself is not responsible for the elevated production and the changing pattern of proteoglycans in long-lasting hepatic injury.
D000818:Animals; D002809:Chondroitin Sulfates / Q000096:biosynthesis; D005944:Glucosamine / Q000378:metabolism; D006025:Glycosaminoglycans / Q000096:biosynthesis*; D006497:Heparan Sulfate / Q000096:biosynthesis; D006595:Hexosamines / Q000378:metabolism; D066298:In Vitro Techniques; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008115:Liver Regeneration; D051381:Rats; D014537:Uridine Diphosphate N-Acetylglucosamine / Q000378:metabolism
D002809:Chondroitin Sulfates; D005944:Glucosamine; D006025:Glycosaminoglycans; D006497:Heparan Sulfate; D006595:Hexosamines; D014537:Uridine Diphosphate N-Acetylglucosamine